Communications methods, methods of forming a reader, wireless communications readers, and wireless communications systems

ABSTRACT

Communications methods, methods of forming a reader, wireless communications readers, and wireless communications systems are described in some embodiments. In one embodiment, a communications method includes associating a plurality of remote communications devices with a plurality of objects located within a wireless communications range of a reader having a first configuration, providing one of the remote communications device within a wireless communications range of a reader having a second configuration, wherein the wireless communications range of the reader having the second configuration is less than the wireless communications range of the reader having the first configuration, and during the presence of the one of the remote communications devices within the wireless communications range of the reader having the second configuration, implementing communications between the reader having the second configuration and only the one of the remote communications devices.

TECHNICAL FIELD

The technical field is communications methods, methods of forming areader, wireless communications readers, and wireless communicationssystems.

BACKGROUND

Wireless communications systems which include a plurality ofcommunications devices are useful in various systems and applications.For example, wireless communications systems may be used in applicationswhere identification of objects is desired. A respective wirelesscommunications system may include a base device which communicates withone or more tags which may be associated with one or more objects to beidentified.

In some wireless communications system arrangements, the number of tagsused may be significant if there are numerous objects to be monitored.In addition, improvements have been made in some configurations toextend a range of the wireless communications. As a result, someconfigurations utilize relatively sophisticated designs to providediscrimination during identification of devices which may becommunicating at the same moment in time resulting in collisions. Thesedesigns may also have other drawbacks with respect to power consumption,reliability and cost.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a functional block diagram of a wireless communications systemaccording to one embodiment.

FIG. 2 is an illustrative representation of communications devicesaccording to one embodiment.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

Referring to FIG. 1, a wireless communications system 10 is shownaccording to one embodiment. The system 10 includes a reader 12 and aplurality of remote communications devices 14. Reader 12 includesantenna 32 and is configured to implement wireless communications 13including bi-directional communications with one or more of devices 14in one embodiment. Remote communications devices 14 may be referred toas tags and may be associated with objects (e.g., merchandise, cargo,animals, or other articles). Wireless communications 13 may includeelectromagnetic signals, optical signals, or acoustic signals in someembodiments. The reader 12 and/or one or more of the remotecommunications devices 14 may be movable relative to one another, andaccordingly, the number of remote communications devices 14 within acommunications range of reader 12 may change at different moments intime. The devices 14 may be VHF, UHF or microwave devices and maycommunicate microwave electromagnetic signals (e.g., 915 MHz) in someembodiments.

The wireless communications 13 may include wireless signals comprisinginformation or data to be communicated. Wireless communications system10 is configured to implement identification operations in oneembodiment. Reader 12 may output commands which are processed byrespective devices 14 and which may cause devices 14 to perform one ormore desired functions. In one identification embodiment, reader 12interrogates wireless communications devices 14 wherein the reader 12outputs an interrogation signal requesting all receiving devices 14 torespond. Remote communications devices 14 which are present within thecommunications range of reader 12 receive and process the outputtedsignal, and the respective devices 14 may formulate and communicatereplies or other messages in the form of wireless signals which mayinclude respective identifiers which uniquely identify respective onesof the remote communications devices 14. In some embodiments, objects,such as inventory items, may be associated with the devices 14 and thedescribed identification operations may operate to additionally identifythe objects as well as the devices 14. Wireless communications system 10configured to implement identification operations may be referred to asa Radio Frequency Identification (RFID) system in one embodiment.

In one embodiment, wireless communications system 10 may utilize aplurality of readers 12 having different configurations, or a singlereader 12 capable of operating in a plurality of configurations. Forexample, in some wireless communications embodiments, system 10 mayexperience collisions of signals simultaneously communicated by numerousdevices 14 responding to an interrogation signal. The signal collisionsmay make it difficult to identify which devices 14 responded. Also, dueto increased range of some reader embodiments, a user of reader 12 maynot be sure which particular device 14 responds to an interrogationsignal.

Accordingly, in one embodiment, readers 12 having differentconfigurations may be used (e.g., a single reader configurable betweendifferent configurations, or a plurality of readers having differentconfigurations). The different configurations have different associatedcommunications ranges in one embodiment. In one configuration, reader 12may be configured for increased range to enable communications withdevices 14 present within a respective area to be monitored. In oneembodiment, reader 12 of increased range may be used to communicate withplural devices 14 (and perhaps objects associated with the devices 14)located within a warehouse. The reader 12 of increased range may beconfigured to discriminate communications of plural devices 14 and/orimplement communications at increased power levels to performcommunications within the increased range.

Another configuration of reader 12 having a decreased communicationsrange may be used at other moments in time. In one embodiment, reader 12of decreased range is configured to communicate within an area which isless than an area associated with the communications range of the reader12 of increased range. In one embodiment, reader 12 of increased rangemay communicate with devices 14 located at distances of a meter or morefrom reader 12, while reader 12 of decreased range may communicate withdevices 14 located at distances of a few inches or less from reader 12.As described with respect to the various embodiments below, reader 12 ofincreased range may be referred to as an increased range reader andreader 12 of decreased range may be referred to as a decreased rangereader 12. The decreased range reader 12 may be used by a user wantingto read a specific one of the devices 14, to avoid collisions withnumerous devices 14 (which may also increase power consumption of suchdevices 14), conserve power consumption of reader 12, or for otherreasons. In one embodiment, a user may use readers having the increasedrange and the decreased range configurations at different moments intime to communicate in the same area (e.g., warehouse) with respect toone or more of the same devices 14 present in the area.

Different configurations of decreased range readers are contemplatedaccording to different embodiments. As discussed herein, wirelesscommunications 13 may be utilized to implement communications betweenremote communications device 14 and reader 12. The devices 14 (andincreased range reader 12) may be tuned to a common frequency toimplement wireless communications (and the increased range reader may bereferred to as a tuned reader). In one decreased range embodiment, adecreased range reader 12 may be tuned to a frequency different than thecommon frequency to reduce the communications range of reader 12 (andthe decreased range reader may be referred to as a detuned reader). Inanother embodiment, a decreased range reader 12 may be configured totransmit wireless communications 13 at reduced transmit power (comparedwith transmission powers of increased range readers 12) to reduce thecommunications range of reader 12. The transmission power may be reducedby a factor of 10 or 100 in some examples of decreasing thecommunications range by reducing transmission power of reader 12. Otherembodiments of decreased range readers 12 communicate by contact (e.g.,probes in FIG. 2) with remote communications devices 14 instead of usingwireless communications 13. Other configurations for providing decreasedrange readers 12 are contemplated in other embodiments.

Still referring to FIG. 1, the depicted embodiment of reader 12 includesa communications interface 20, communications circuitry 22, storagecircuitry 24, processing circuitry 26 and a user interface 28. Thedepicted reader 12 may correspond to readers of one or both of theabove-mentioned different configurations. Other configurations of reader12 are possible including more, less and/or alternative components.

Communications interface 20 is arranged to implement communications ofreader 12 with respect to external devices (not shown), such as acomputer. Communications interface 20 may be arranged to communicateinformation bi-directionally with respect to external devices in oneembodiment. Communications interface 20 may be implemented as a networkinterface card, serial or parallel connection, USB port, Firewireinterface, flash memory interface, floppy disk drive, or any othersuitable arrangement for communicating with respect to the externaldevices.

Communications circuitry 22 is configured to communicate with remotecommunications devices 14. In one embodiment, communications circuitry22 includes a transceiver configured to transmit and receive wirelesscommunications 13. In one embodiment, communications circuitry 22 isconfigured to modulate a carrier signal to transmit the wirelesssignals. Communications circuitry 22 may receive signals from devices 14which may include backscattered signals. In one embodiment,communications circuitry 22 is configured to output continuous wave (CW)electromagnetic energy which may be backscattered by devices 14 duringcommunication of response signals. Communications circuitry 22 includesmatching circuitry 30 and antenna 32 in the depicted embodiment.Matching circuitry 30 may include a plurality of discrete components(e.g., capacitors and inductors) configured to transfer electricalenergy intermediate antenna 32 and modulation or demodulation circuitry(not shown) of communications circuitry 30 in one embodiment.

The storage circuitry 24 is configured to store programming such asexecutable code or instructions (e.g., software and/or firmware),electronic data, databases, or other digital information and may includeprocessor-usable media. Processor-usable media may be embodied in anycomputer program product(s) or article of manufacture(s) which cancontain, store, or maintain programming, data and/or digital informationfor use by or in connection with an instruction execution systemincluding processing circuitry 26 in one embodiment. Processor-usablemedia may include any one of physical media such as electronic,magnetic, optical, electromagnetic, infrared or semiconductor media.Processor-usable media include in various configurations a portablemagnetic computer diskette, such as a floppy diskette, zip disk, harddrive, random access memory, read only memory, flash memory, cachememory, and/or other configurations capable of storing programming,data, or other digital information.

In one embodiment, processing circuitry 26 is arranged to process data,control data access and storage, issue commands, and control otherdesired operations of reader 12. Processing circuitry 26 is configuredto control the generation of interrogation signals by reader 12 and toprocess response signals received by reader 12 in one embodiment.Processing circuitry 26 may comprise circuitry configured to implementdesired programming provided by appropriate media in at least oneembodiment. The processing circuitry 26 may be implemented as one ormore of a processor and/or other structure configured to executeexecutable instructions including, for example, software and/or firmwareinstructions, and/or hardware circuitry. Some embodiments of processingcircuitry 26 include hardware logic, PGA, FPGA, ASIC, state machines,and/or other structures alone or in combination with a processor. Theseexamples of processing circuitry 26 are for illustration and otherconfigurations are possible.

At least some embodiments may be implemented using programming storedwithin appropriate storage circuitry 24 described above and/orcommunicated via a network or other transmission media and configured tocontrol appropriate processing circuitry 26. For example, programmingmay be provided via appropriate media including, for example, embodiedwithin articles of manufacture, embodied within a data signal (e.g.,modulated carrier wave, data packets, digital representations, etc.)communicated via an appropriate transmission medium, such as acommunication network (e.g., the Internet and/or a private network),wired electrical connection, optical connection and/or electromagneticenergy, for example, via communications interface 20, or provided usingother appropriate communication structure or medium. Programmingincluding processor-usable code may be communicated as a data signalembodied in a carrier wave in one embodiment.

User interface 28 is configured to interact with a user includingconveying data to a user (e.g., displaying data for observation by theuser), as well as receiving inputs from the user (e.g., tactile input).Accordingly, in one embodiment, the user interface 28 may include adisplay configured to depict visual information and a keyboard or otherinput device. Any other suitable apparatus for interacting with a usermay also be utilized. A user may exercise control over a command setusing user interface 28 to implement operations of reader 12 in oneembodiment.

Remote communications devices 14 may be individually associated with anobject as mentioned above and may be configured to output responsesignals which may include identifiers configured to uniquely identifythe respective communicating devices 14 (and, optionally associatedobjects). Remote communications devices 14 may be configured in passivearrangements wherein the devices 14 have no on-board power supplies butderive electrical energy to power circuitry of devices 14 as well asimplement wireless communications (e.g., backscattered response signals)using received electromagnetic energy. Remote communications devices 14may also be implemented in semi-passive arrangements wherein the devices14 individually include a power source, such as a battery, configured topower circuitry of the respective device 14 while response signals arecommunicated using received electromagnetic energy (e.g.,backscattered). Remote communications devices 14 may also be implementedin active arrangements wherein the devices 14 individually include apower source, such as a battery, configured to power circuitry of therespective device 14 as well as provide communications of responsesignals (e.g., modulating a carrier signal generated using an activetransmitter of the respective device 14).

In one embodiment, remote communications devices 14 are configured toimplement wireless communications 13 at a desired frequency which may bereferred to as a communications frequency. The wireless communications13 may include wireless signals individually utilizing a carrier signalof the respective frequency or continuous wave electromagnetic energy ofthe respective frequency in one embodiment. Remote communicationsdevices 14 configured to implement communications at the desiredfrequency may be tuned to the respective frequency in one embodiment. Inone embodiment, the remote communications devices 14 may individuallycomprise communications circuitry configured to resonate at therespective frequency in one embodiment (e.g., an antenna and/ormodulation/demodulation circuitry of a remote communications device notshown in FIG. 1 may be configured to communicate at the respectivefrequency). It is desired in one embodiment to tune the remotecommunications devices 14 to the communications frequency being utilizedto enable wireless communications 13 of increased range compared toconfigurations which are not tuned to the respective communicationsfrequency.

As mentioned above, different configurations of reader(s) 12 may be usedto implement desired types of communications with respect to remotecommunications devices 14 of the system 10. An increased range reader 12may be tuned to the respective frequency of wireless communications 13to provide wireless communications 13 of an increased communicationsrange (e.g., >1 meter) compared with a communications range of adecreased range reader 12 (e.g., <1 inch) not tuned to the frequency ofwireless communications 13, communicating at lower power, and/orconfigured in other ways to communicate at reduced ranges.

In one embodiment, communications circuitry 22 of the increased rangereader 12 is tuned to resonate at the respective frequency of wirelesscommunications 13. The antenna 32 and matching circuitry 30 (if present)of communications circuitry 22 are tuned to the respective frequency inone embodiment. In a more specific embodiment, the length of the antenna32 may be designed according to the wavelength of the frequency ofwireless communications 13 and the values of one or more discretecomponent of matching circuitry 30 may be selected to provide increasedtransfer of power intermediate antenna 32 and remaining portions ofcommunications circuitry 22.

As mentioned above, the increased range reader 12 has a communicationsrange covering a larger area than a communications range of a decreasedrange reader 12. The increased range reader 12 may simultaneouslyestablish an electrical field coupling (with minimal or no magneticfield coupling in one embodiment) with plural devices 14 to implementwireless communications 13 in one embodiment. The decreased rangereaders 12 are configured to communicate at reduced wirelesscommunication ranges or by contact. As mentioned above, decreased rangereaders 12 may be detuned and/or configured to communicate at reducedtransmit power levels. In one detuned embodiment, a decreased rangereader 12 may be detuned in various ways to establish an electricalfield coupling with only one of the devices 14 at a given moment in timein one embodiment. For example, antenna 32 may be selected to notcorrespond to the frequency of wireless communications 13. In oneembodiment, the length of the antenna 32 may be mismatched with respectto a wavelength or any integer fractional multiple of the wavelength ofthe frequency of the wireless communications 13. In one example, aremote communications device 14 may have a dipole antenna ofapproximately 3″ in length (e.g., attached to a substrate ofapproximately 3″ by 4″) corresponding to the communications frequency ofwireless communications 13 while antenna 32 configured as a dipoleantenna in one embodiment has a length of approximately 1″ or less.Other types of antenna 32, such as sub-quarter wavelength loops andpatches, may be used (and configured to be inefficient if desired). Inone embodiment, it is desired to detune a sensitivity of antenna 32 by10 dB or more.

In another embodiment of implementing a decreased range reader 12 bydetuning, matching circuitry 30 may be intentionally designed to provideless than maximum power transfer intermediate antenna 32 and otherportions (e.g., modulation or demodulation circuitry) of communicationscircuitry 32. In one embodiment, inductors and/or capacitors ofdifferent values may be used to decrease efficiency of power transfer.Other embodiments of reader 12 having a detuned configuration may beused.

In one embodiment, a plurality of readers 12 having one of the increasedrange configuration and decreased range configuration may be provided ina given wireless communications system 10 to implement communicationswithin respective communications ranges. In another embodiment, a singlereader 12 may be configured at different moments in time “on-the-fly”between increased and decreased range configurations. In someembodiments, a user may change a configuration of matching circuitry 30(e.g., adjusting a value of a component of circuitry 30), switch betweenuse of a provided increased range (tuned) antenna and a differentdecreased range (detuned) antenna and/or change transmit power levelsbetween respective ones of the increased and decreased rangeconfigurations at different moments in time.

In one embodiment, reader 12 having a decreased range configuration isonly configured to communicate with one of the remote communicationsdevices 14 at a given moment in time. A user may desire to use reader 12having a reduced range configuration at certain moments in time or toperform certain operations and which may provide improved operationcompared with a reader 12 having an increased range configuration. Forexample, the user may use reader 12 having the decreased rangeconfiguration to ensure the reader 12 is communicating with a known oneof the remote communications devices 14 by placing a portable (e.g.,handheld) decreased range reader 12 in close proximity to the respectiveindividual device 14 (e.g., less than 1″). In one embodiment, theplacement of reader 12 having a decreased range configuration adjacentto respective ones of the devices 14 to read the respective devices 14at different moments in time provides manual singulation with respect toreading devices 14. Accordingly, identification of a communicatingdevice 14 may be established without the use of arbitration ordiscrimination circuitry which discriminates wireless signals frommultiple sources which collide. In another embodiment, devices 14 may beindividually proximately placed at different moments in time adjacent toreader 12 having the decreased range configuration. The reader 12 may bere-configured to an increased range configuration or another reader 12having an increased range configuration may be used at another moment intime if desired to communicate with plural devices 14 of the system 10and perhaps with respect to devices 14 spaced at increased distancesrelative to the increased range reader 12.

Referring to FIG. 2, one embodiment of a decreased range reader 12communicating with an individual one of the remote communicationsdevices 14 is shown. The communications circuitry 22 of the illustratedreader 12 includes a probe comprising a plurality of electricalconnections 38 which are configured to physically touch and establishelectrical contact with conductors of a given device 14. In oneembodiment, the electrical connections 38 of probe may contactrespective halves of a dipole antenna 42, leads of antenna 42, padscoupled with antenna 42 (and perhaps integrated circuitry 40 of device14 including processing circuitry and storage circuitry configuredsimilarly to processing circuitry and communications circuitry describedabove in one embodiment), or other desired electrical connections of thedevice 14 to enable communication of electrical signals between reader12 and device 14. Tips of electrical connections 38 may be pointed toensure sufficient pressure contact during operation or to penetrate anelectrically insulative housing material of device 14 (if present). Thearrangement of reader 12 shown in FIG. 2 may be useful in applicationswhere devices 14 are closely positioned with respect to one another orwherein the devices 14 are relatively inaccessible to an entirety of thereader 12 itself.

As described herein, at some moments in time, it may be desired toprovide communications of system 10 in a range less than a wirelesscommunications range otherwise achievable by the system 10. For example,in one access control application, it is desired to make sure thatreader 12 reads a device 14 associated with a party desiring to achieveaccess to a secured area and not another device 14 of a different party14 who may also be present. Decreased range communications may also beused to insure communications with one desired device 14 in the presenceof many other devices 14 associated with numerous objects in inventory.Readers 12 of decreased range configurations may be desired overincreased range readers 12 with respect to reduced power requirements,utilization of less sensitive receive circuitry, utilization of antennaeof less efficiency, more compact size, less sophistication (e.g., nosingulation, arbitration or sorting processing capabilities), increasedreliability and/or reduced cost.

In compliance with the statute, the subject matter disclosed herein hasbeen described in language more or less specific as to structural andmethodical features. It is to be understood, however, that the claimsare not limited to the specific features shown and described, since themeans herein disclosed comprise only some of the various contemplatedembodiments. The claims are thus to be afforded full scope as literallyworded, and to be appropriately interpreted in accordance with thedoctrine of equivalents.

Further, details herein have been presented for guidance in constructionand/or operation of the disclosed embodiments. Applicant(s) hereofconsider these described embodiments to also include, disclose anddescribe further arrangements or embodiments in addition to thoseexplicitly disclosed. For example, the additional embodiments mayinclude less, more and/or alternative features than those described inthe specifically described embodiments. More specifically, Applicantsconsider the disclosure to include, disclose and describe methods whichinclude less, more and/or alternative acts than those methods explicitlydisclosed as well as apparatus which includes less, more and/oralternative structure than the explicitly disclosed structures.

1. A communications method comprising: using a reader having a firstconfiguration, outputting a first wireless interrogation signal in anarea corresponding to a first wireless communications range of thereader having the first configuration; receiving the first wirelessinterrogation signal using a plurality of remote communications deviceslocated in the first wireless communications range; using the reader,receiving a plurality of wireless response signals from the remotecommunications devices which received the first wireless interrogationsignal; changing the reader from the first configuration to a secondconfiguration that is different than the first configuration;positioning the reader having the second configuration in proximity toone of the remote communications devices located in the area, whereinthe reader having the second configuration communicates within a secondwireless communications range that is smaller than the first wirelesscommunications range; outputting a second interrogation signal from thereader having the second configuration; receiving the secondinterrogation signal using the one of the remote communications devices;and after receiving the second interrogation signal and using the readerhaving the second configuration, receiving another response signalsolely from the one of the remote communications devices and from noothers of the remote communications devices located in the area.
 2. Themethod of claim 1 wherein the positioning establishes an electricalfield coupling of the reader with only the one of the remotecommunications devices.
 3. The method of claim 1 wherein the positioningestablishes electrical contact of the reader with only the one of theremote communications devices.
 4. The method of claim 1 wherein theremote communications devices are tuned to a communications frequency.5. The method of claim 4 wherein the communications frequencycorresponds to a frequency of a carrier signal comprising a microwavesignal.
 6. The method of claim 1 wherein the outputting the first signalcomprises outputting at a greater transmit power than the outputting thesecond signal.
 7. The method of claim 1 wherein the positioningcomprises positioning the reader to provide the one of the remotecommunications devices within the second wireless communications range.8. The method of claim 1 wherein the receiving the first signalcomprises receiving the first signal using the remote communicationsdevices comprising tags.
 9. The method of claim 1 wherein the receivingthe wireless response signals comprises receiving the wireless responsesignals configured to identify respective ones of the remotecommunications devices.
 10. The method of claim 1 wherein the receivingsof the wireless response signals and the another response signalcomprise receiving the wireless and the another response signalsindividually comprising backscattered signals.
 11. The method of claim 1further comprising positioning the reader in proximity to individualones of others of the remote communications devices at other moments intime.